DfpField (Apache Commons Math 3.6.1 API)

java.lang.Object
- org.apache.commons.math3.dfp.DfpField

All Implemented Interfaces:

Field<Dfp>
```
public class DfpField
extends Object
implements Field<Dfp>
```
Field for Decimal floating point instances.

Since:

2.2

Nested Class Summary

Nested Classes
Modifier and Type Class and Description

static class DfpField.RoundingMode
Enumerate for rounding modes.

Nested Classes
Modifier and Type	Class and Description
`static class`	`DfpField.RoundingMode` Enumerate for rounding modes.

Field Summary

Fields
Modifier and Type	Field and Description
`static int`	`FLAG_DIV_ZERO` IEEE 854-1987 flag for division by zero.
`static int`	`FLAG_INEXACT` IEEE 854-1987 flag for inexact result.
`static int`	`FLAG_INVALID` IEEE 854-1987 flag for invalid operation.
`static int`	`FLAG_OVERFLOW` IEEE 854-1987 flag for overflow.
`static int`	`FLAG_UNDERFLOW` IEEE 854-1987 flag for underflow.

Constructor Summary

Constructors
Constructor and Description

DfpField(int decimalDigits)
Create a factory for the specified number of radix digits.

Constructors
Constructor and Description
`DfpField(int decimalDigits)` Create a factory for the specified number of radix digits.

Method Summary

Methods
Modifier and Type	Method and Description
`void`	`clearIEEEFlags()` Clears the IEEE 854 status flags.
`static Dfp`	`computeExp(Dfp a, Dfp one)` Compute exp(a).
`static Dfp`	`computeLn(Dfp a, Dfp one, Dfp two)` Compute ln(a).
`Dfp`	`getE()` Get the constant e.
`Dfp[]`	`getESplit()` Get the constant e split in two pieces.
`int`	`getIEEEFlags()` Get the IEEE 854 status flags.
`Dfp`	`getLn10()` Get the constant ln(10).
`Dfp`	`getLn2()` Get the constant ln(2).
`Dfp[]`	`getLn2Split()` Get the constant ln(2) split in two pieces.
`Dfp`	`getLn5()` Get the constant ln(5).
`Dfp[]`	`getLn5Split()` Get the constant ln(5) split in two pieces.
`Dfp`	`getOne()` Get the constant 1.
`Dfp`	`getPi()` Get the constant π.
`Dfp[]`	`getPiSplit()` Get the constant π split in two pieces.
`int`	`getRadixDigits()` Get the number of radix digits of the `Dfp` instances built by this factory.
`DfpField.RoundingMode`	`getRoundingMode()` Get the current rounding mode.
`Class<? extends FieldElement<Dfp>>`	`getRuntimeClass()` Returns the runtime class of the FieldElement.
`Dfp`	`getSqr2()` Get the constant √2.
`Dfp`	`getSqr2Reciprocal()` Get the constant √2 / 2.
`Dfp[]`	`getSqr2Split()` Get the constant √2 split in two pieces.
`Dfp`	`getSqr3()` Get the constant √3.
`Dfp`	`getSqr3Reciprocal()` Get the constant √3 / 3.
`Dfp`	`getTwo()` Get the constant 2.
`Dfp`	`getZero()` Get the constant 0.
`Dfp`	`newDfp()` Makes a `Dfp` with a value of 0.
`Dfp`	`newDfp(byte x)` Create an instance from a byte value.
`Dfp`	`newDfp(byte sign, byte nans)` Creates a `Dfp` with a non-finite value.
`Dfp`	`newDfp(Dfp d)` Copy constructor.
`Dfp`	`newDfp(double x)` Create an instance from a double value.
`Dfp`	`newDfp(int x)` Create an instance from an int value.
`Dfp`	`newDfp(long x)` Create an instance from a long value.
`Dfp`	`newDfp(String s)` Create a `Dfp` given a String representation.
`void`	`setIEEEFlags(int flags)` Sets the IEEE 854 status flags.
`void`	`setIEEEFlagsBits(int bits)` Sets some bits in the IEEE 854 status flags, without changing the already set bits.
`void`	`setRoundingMode(DfpField.RoundingMode mode)` Set the rounding mode.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - FLAG_INVALID
```
public static final int FLAG_INVALID
```
    IEEE 854-1987 flag for invalid operation.
    
    See Also:
    Constant Field Values
  - FLAG_DIV_ZERO
```
public static final int FLAG_DIV_ZERO
```
    IEEE 854-1987 flag for division by zero.
    
    See Also:
    Constant Field Values
  - FLAG_OVERFLOW
```
public static final int FLAG_OVERFLOW
```
    IEEE 854-1987 flag for overflow.
    
    See Also:
    Constant Field Values
  - FLAG_UNDERFLOW
```
public static final int FLAG_UNDERFLOW
```
    IEEE 854-1987 flag for underflow.
    
    See Also:
    Constant Field Values
  - FLAG_INEXACT
```
public static final int FLAG_INEXACT
```
    IEEE 854-1987 flag for inexact result.
    
    See Also:
    Constant Field Values
- Constructor Detail
  - DfpField
```
public DfpField(int decimalDigits)
```
    Create a factory for the specified number of radix digits.
    Note that since the Dfp class uses 10000 as its radix, each radix digit is equivalent to 4 decimal digits. This implies that asking for 13, 14, 15 or 16 decimal digits will really lead to a 4 radix 10000 digits in all cases.
    
    Parameters:
    decimalDigits - minimal number of decimal digits.
- Method Detail
  - getRadixDigits
```
public int getRadixDigits()
```
    Get the number of radix digits of the Dfp instances built by this factory.
    
    Returns:
    number of radix digits
  - setRoundingMode
```
public void setRoundingMode(DfpField.RoundingMode mode)
```
    Set the rounding mode. If not set, the default value is DfpField.RoundingMode.ROUND_HALF_EVEN.
    
    Parameters:
    mode - desired rounding mode Note that the rounding mode is common to all Dfp instances belonging to the current DfpField in the system and will affect all future calculations.
  - getRoundingMode
```
public DfpField.RoundingMode getRoundingMode()
```
    Get the current rounding mode.
    
    Returns:
    current rounding mode
  - getIEEEFlags
```
public int getIEEEFlags()
```
    Get the IEEE 854 status flags.
    
    Returns:
    IEEE 854 status flags
    See Also:
    clearIEEEFlags(), setIEEEFlags(int), setIEEEFlagsBits(int), FLAG_INVALID, FLAG_DIV_ZERO, FLAG_OVERFLOW, FLAG_UNDERFLOW, FLAG_INEXACT
  - clearIEEEFlags
```
public void clearIEEEFlags()
```
    Clears the IEEE 854 status flags.
    
    See Also:
    getIEEEFlags(), setIEEEFlags(int), setIEEEFlagsBits(int), FLAG_INVALID, FLAG_DIV_ZERO, FLAG_OVERFLOW, FLAG_UNDERFLOW, FLAG_INEXACT
  - setIEEEFlags
```
public void setIEEEFlags(int flags)
```
    Sets the IEEE 854 status flags.
    
    Parameters:
    flags - desired value for the flags
    See Also:
    getIEEEFlags(), clearIEEEFlags(), setIEEEFlagsBits(int), FLAG_INVALID, FLAG_DIV_ZERO, FLAG_OVERFLOW, FLAG_UNDERFLOW, FLAG_INEXACT
  - setIEEEFlagsBits
```
public void setIEEEFlagsBits(int bits)
```
    Sets some bits in the IEEE 854 status flags, without changing the already set bits.
    Calling this method is equivalent to call setIEEEFlags(getIEEEFlags() | bits)
    
    Parameters:
    bits - bits to set
    See Also:
    getIEEEFlags(), clearIEEEFlags(), setIEEEFlags(int), FLAG_INVALID, FLAG_DIV_ZERO, FLAG_OVERFLOW, FLAG_UNDERFLOW, FLAG_INEXACT
  - newDfp
```
public Dfp newDfp()
```
    Makes a Dfp with a value of 0.
    
    Returns:
    a new Dfp with a value of 0
  - newDfp
```
public Dfp newDfp(byte x)
```
    Create an instance from a byte value.
    
    Parameters:
    x - value to convert to an instance
    
    Returns:
    a new Dfp with the same value as x
  - newDfp
```
public Dfp newDfp(int x)
```
    Create an instance from an int value.
    
    Parameters:
    x - value to convert to an instance
    
    Returns:
    a new Dfp with the same value as x
  - newDfp
```
public Dfp newDfp(long x)
```
    Create an instance from a long value.
    
    Parameters:
    x - value to convert to an instance
    
    Returns:
    a new Dfp with the same value as x
  - newDfp
```
public Dfp newDfp(double x)
```
    Create an instance from a double value.
    
    Parameters:
    x - value to convert to an instance
    
    Returns:
    a new Dfp with the same value as x
  - newDfp
```
public Dfp newDfp(Dfp d)
```
    Copy constructor.
    
    Parameters:
    d - instance to copy
    
    Returns:
    a new Dfp with the same value as d
  - newDfp
```
public Dfp newDfp(String s)
```
    Create a Dfp given a String representation.
    
    Parameters:
    s - string representation of the instance
    
    Returns:
    a new Dfp parsed from specified string
  - newDfp
```
public Dfp newDfp(byte sign,
         byte nans)
```
    Creates a Dfp with a non-finite value.
    
    Parameters:
    sign - sign of the Dfp to create
    nans - code of the value, must be one of Dfp.INFINITE, Dfp.SNAN, Dfp.QNAN
    
    Returns:
    a new Dfp with a non-finite value
  - getZero
```
public Dfp getZero()
```
    Get the constant 0.
    
    Specified by:
    
    getZero in interface Field<Dfp>
    
    Returns:
    a Dfp with value 0
  - getOne
```
public Dfp getOne()
```
    Get the constant 1.
    
    Specified by:
    
    getOne in interface Field<Dfp>
    
    Returns:
    a Dfp with value 1
  - getRuntimeClass
```
public Class<? extends FieldElement<Dfp>> getRuntimeClass()
```
    Returns the runtime class of the FieldElement.
    
    Specified by:
    
    getRuntimeClass in interface Field<Dfp>
    
    Returns:
    The Class object that represents the runtime class of this object.
  - getTwo
```
public Dfp getTwo()
```
    Get the constant 2.
    
    Returns:
    a Dfp with value 2
  - getSqr2
```
public Dfp getSqr2()
```
    Get the constant √2.
    
    Returns:
    a Dfp with value √2
  - getSqr2Split
```
public Dfp[] getSqr2Split()
```
    Get the constant √2 split in two pieces.
    
    Returns:
    a Dfp with value √2 split in two pieces
  - getSqr2Reciprocal
```
public Dfp getSqr2Reciprocal()
```
    Get the constant √2 / 2.
    
    Returns:
    a Dfp with value √2 / 2
  - getSqr3
```
public Dfp getSqr3()
```
    Get the constant √3.
    
    Returns:
    a Dfp with value √3
  - getSqr3Reciprocal
```
public Dfp getSqr3Reciprocal()
```
    Get the constant √3 / 3.
    
    Returns:
    a Dfp with value √3 / 3
  - getPi
```
public Dfp getPi()
```
    Get the constant π.
    
    Returns:
    a Dfp with value π
  - getPiSplit
```
public Dfp[] getPiSplit()
```
    Get the constant π split in two pieces.
    
    Returns:
    a Dfp with value π split in two pieces
  - getE
```
public Dfp getE()
```
    Get the constant e.
    
    Returns:
    a Dfp with value e
  - getESplit
```
public Dfp[] getESplit()
```
    Get the constant e split in two pieces.
    
    Returns:
    a Dfp with value e split in two pieces
  - getLn2
```
public Dfp getLn2()
```
    Get the constant ln(2).
    
    Returns:
    a Dfp with value ln(2)
  - getLn2Split
```
public Dfp[] getLn2Split()
```
    Get the constant ln(2) split in two pieces.
    
    Returns:
    a Dfp with value ln(2) split in two pieces
  - getLn5
```
public Dfp getLn5()
```
    Get the constant ln(5).
    
    Returns:
    a Dfp with value ln(5)
  - getLn5Split
```
public Dfp[] getLn5Split()
```
    Get the constant ln(5) split in two pieces.
    
    Returns:
    a Dfp with value ln(5) split in two pieces
  - getLn10
```
public Dfp getLn10()
```
    Get the constant ln(10).
    
    Returns:
    a Dfp with value ln(10)
  - computeExp
```
public static Dfp computeExp(Dfp a,
             Dfp one)
```
    Compute exp(a).
    
    Parameters:
    a - number for which we want the exponential
    one - constant with value 1 at desired precision
    
    Returns:
    exp(a)
  - computeLn
```
public static Dfp computeLn(Dfp a,
            Dfp one,
            Dfp two)
```
    Compute ln(a). Let f(x) = ln(x), We know that f'(x) = 1/x, thus from Taylor's theorem we have: ----- n+1 n f(x) = \ (-1) (x - 1) / ---------------- for 1 <= n <= infinity ----- n or 2 3 4 (x-1) (x-1) (x-1) ln(x) = (x-1) - ----- + ------ - ------ + ... 2 3 4 alternatively, 2 3 4 x x x ln(x+1) = x - - + - - - + ... 2 3 4 This series can be used to compute ln(x), but it converges too slowly. If we substitute -x for x above, we get 2 3 4 x x x ln(1-x) = -x - - - - - - + ... 2 3 4 Note that all terms are now negative. Because the even powered ones absorbed the sign. Now, subtract the series above from the previous one to get ln(x+1) - ln(1-x). Note the even terms cancel out leaving only the odd ones 3 5 7 2x 2x 2x ln(x+1) - ln(x-1) = 2x + --- + --- + ---- + ... 3 5 7 By the property of logarithms that ln(a) - ln(b) = ln (a/b) we have: 3 5 7 x+1 / x x x \ ln ----- = 2 * | x + ---- + ---- + ---- + ... | x-1 \ 3 5 7 / But now we want to find ln(a), so we need to find the value of x such that a = (x+1)/(x-1). This is easily solved to find that x = (a-1)/(a+1).
    
    Parameters:
    a - number for which we want the exponential
    one - constant with value 1 at desired precision
    two - constant with value 2 at desired precision
    
    Returns:
    ln(a)

Class DfpField

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

FLAG_INVALID

FLAG_DIV_ZERO

FLAG_OVERFLOW

FLAG_UNDERFLOW

FLAG_INEXACT

Constructor Detail

DfpField

Method Detail

getRadixDigits

setRoundingMode

getRoundingMode

getIEEEFlags

clearIEEEFlags

setIEEEFlags

setIEEEFlagsBits

newDfp

newDfp

newDfp

newDfp

newDfp

newDfp

newDfp

newDfp

getZero

getOne

getRuntimeClass

getTwo

getSqr2

getSqr2Split

getSqr2Reciprocal

getSqr3

getSqr3Reciprocal

getPi

getPiSplit

getE

getESplit

getLn2

getLn2Split

getLn5

getLn5Split

getLn10

computeExp

computeLn